With cheeseburgers and beer for breakfast, Matthew McConaughey had a lot of fun transforming his figure for his latest film, but the true draw was the chance to inhabit a real person. By Gemma Dunn

When Matthew McConaughey lost around 20 kg for his show-stopping portrayal of Aids sufferer Ron Woodroof in 2013’s Dallas Buyers Club, it was a make-under that drew gasps. The former romcom king had ditched the tried-and-tested heart- throb tag, growing into a truly gifted artist. A move – brilliantly dubbed ‘the McConaissance’ – that subsequently earned him his first Oscar.

Four years on, and McConaughey has attracted critical acclaim for his role opposite Woody Harrelson in HBO series True Detective, and impressed in Christopher Nolan’s sci-fi blockbuster Interstellar, securing his spot among Hollywood’s greatest.

His latest incarnation is as Kenny Wells: a balding, overweight gold-mine prospector at the heart of director Stephen Gaghan’s latest big-screen epic, Gold. Inspired by actual events and set in South East Asia, the crime-adventure movie follows the ambitious tale of one man’s American dream – and everything that he will do to keep it from falling apart. Intrigued by the concept of how far one man would go, it’s a role that McConaughey just couldn’t turn down.

‘Kenny had a literal dream that he knew somebody that knew where the gold was, and he took a one-way ticket to Indonesia to chase that dream down and make it so,’ says the 47-year-old actor, who’s also currently lending his voice to musical animated film Sing.

‘I don’t have – that I can think of – such specific dreams. I try to go about my life every day to keep me in the dream, maybe,’ he adds, smiling. ‘But Kenny has nine lives… I don’t think I have cheated death as many times as he has.

Dressed in blue jeans and a dark denim shirt, a heavily bearded McConaughey (legs crossed casually at the knee) is in good spirits. Calm, collected and only too happy to chat. Any questions outside the remit of the film are politely steered back, but he talks with a sincerity and charm that make him instantly likeable (even if his constant eye contact feels slightly intense).

As Wells, McConaughey is almost unrecognisable – the physical transformation this time helped by a customised balding toupee, prosthetic crooked teeth and a 20 kg weight gain – thanks to a diet of beer, cheeseburgers and milkshakes. It was a regime that earned him the title of Captain Fun at home (he lives in his native Texas with his Brazilian model wife, Camila Alves, and their three children – sons Levi and Livingston, and daughter Vida).

While you certainly can’t tell today that McConaughey was ever out of shape, I wonder if his extreme dieting ever gives him cause for concern, long term?

‘I take pretty good care of myself and, even in putting on all the weight or losing all the weight, I am listening to – or I do my best to listen to – my body along the way,’ he says. ‘I think the body is more resilient than a lot of people give it credit for. If anything, I think I looked at it as a possible health benefit to just stretch, so to speak.’

McConaughey explains that he loves to ‘play real people’. ‘That’s part of what is wonderful about my job; doing my best to go and inhabit somebody else. Yes, it is the actor doing it, it’s coming through my vessel, but that’s part of the fun, that’s part of the adventure.

‘My job as an actor is to expose humanity,’ he continues. ‘So I can go into a guy and love inhabiting him and feel like I know him so well and he is a real person. That’s the fun part of what actors get to do.’

He admits that his Academy Award win boosted his faith in his ability to tackle more complex roles. ‘It gave me more confidence in the choices I was making, to keep them very personal for me; to make sure I was still choosing roles that scare me, that I’m not sure how I’m going to pull off but I am going to dive in and give it a punt.’